{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T10:58:26Z","timestamp":1788260306170,"version":"build-2803163510"},"reference-count":47,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2025,8,13]],"date-time":"2025-08-13T00:00:00Z","timestamp":1755043200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Diabetic retinopathy (DR), a leading cause of vision loss worldwide, poses a critical challenge to healthcare systems due to its silent progression and the reliance on labor-intensive, subjective manual screening by ophthalmologists, especially amid a global shortage of eye care specialists. Addressing the pressing need for scalable, objective, and interpretable diagnostic tools, this work introduces RetinoDeep\u2014deep learning frameworks integrating hybrid architectures and explainable AI to enhance the automated detection and classification of DR across seven severity levels. Specifically, we propose four novel models: an EfficientNetB0 combined with an SPCL transformer for robust global feature extraction; a ResNet50 ensembled with Bi-LSTM to synergize spatial and sequential learning; a Bi-LSTM optimized through genetic algorithms for hyperparameter tuning; and a Bi-LSTM with SHAP explainability to enhance model transparency and clinical trustworthiness. The models were trained and evaluated on a curated dataset of 757 retinal fundus images, augmented to improve generalization, and benchmarked against state-of-the-art baselines (including EfficientNetB0, Hybrid Bi-LSTM with EfficientNetB0, Hybrid Bi-GRU with EfficientNetB0, ResNet with filter enhancements, Bi-LSTM optimized using Random Search Algorithm (RSA), Particle Swarm Optimization (PSO), Ant Colony Optimization (ACO), and a standard Convolutional Neural Network (CNN)), using metrics such as accuracy, F1-score, and precision. Notably, the Bi-LSTM with Particle Swarm Optimization (PSO) outperformed other configurations, achieving superior stability and generalization, while SHAP visualizations confirmed alignment between learned features and key retinal biomarkers, reinforcing the system\u2019s interpretability. By combining cutting-edge neural architectures, advanced optimization, and explainable AI, this work sets a new standard for DR screening systems, promising not only improved diagnostic performance but also potential integration into real-world clinical workflows.<\/jats:p>","DOI":"10.3390\/s25165019","type":"journal-article","created":{"date-parts":[[2025,8,13]],"date-time":"2025-08-13T13:30:38Z","timestamp":1755091838000},"page":"5019","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["RetinoDeep: Leveraging Deep Learning Models for Advanced Retinopathy Diagnostics"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9335-1253","authenticated-orcid":false,"given":"Sachin","family":"Kansal","sequence":"first","affiliation":[{"name":"Computer Science Engineering Department, Thapar Institute of Engineering Technology, Patiala 147004, Punjab, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bajrangi Kumar","family":"Mishra","sequence":"additional","affiliation":[{"name":"Civil Engineering Department, Thapar Institute of Engineering Technology, Patiala 147004, Punjab, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saniya","family":"Sethi","sequence":"additional","affiliation":[{"name":"BioTechnology Engineering Department, Thapar Institute of Engineering Technology, Patiala 147004, Punjab, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kanika","family":"Vinayak","sequence":"additional","affiliation":[{"name":"BioTechnology Engineering Department, Thapar Institute of Engineering Technology, Patiala 147004, Punjab, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Priya","family":"Kansal","sequence":"additional","affiliation":[{"name":"Computer Science Engineering Department, Thapar Institute of Engineering Technology, Patiala 147004, Punjab, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2499-6039","authenticated-orcid":false,"given":"Jyotindra","family":"Narayan","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Indian Institute of Technology, Patna 801106, Bihar, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1419","DOI":"10.1007\/s40123-023-00691-3","article-title":"Artificial Intelligence for Diabetic Retinopathy Screening Using Color Retinal Photographs: From Development to Deployment","volume":"12","author":"Grzybowski","year":"2023","journal-title":"Ophthalmol. 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